Water tube boiler construction



Apri 14,-1936. K. L. MAR'N 2,037,424

WATER TUB BOILER CONSTRUCTION Filed Oc.. 9, 1955 y L. MRR TVN IN VEN TOR.

Patented Apr. 14, 1936 UNITED STATES PATENT oFFicE 6 Claims.

'The .invention relates .to steam boilers of the water tube type, and :more especially to those having straight tubes inclined somewhat from the horizontal `with water :compartments at their :ends and one or more steam and water drums yabove the tubes. .It embodies l.improvements in the art of '.ballling this .type .vof :boiler over that disclosed inLmy U. S. Letters Patent No. 1,809,- 133, `issued on June .9, 1931, .and is the result of experience with that construction.

The .improvement consistsin stream lining .and arranging .the baiiles so as; `(1') .to vdecrease .the resistance tothe ilow .of gases .through the boiler, thereby increasing the vcapacitynf the boiler with the chimney .draft zavailable; `(2) :to eliminate angles and :corners which create eddy currents interfering with the gas ilow; (B.) .to eliminate .dead pockets where the gas .does :not circulate, and in which vsoot,cinders `and-ily ash accumulate; and (4) to increase the efficiency .of .the boiler by insuring rapid .flow 'of hot gases .over practically the whole .heating surfaceof the .boil- Aer with a minimum draft loss through the boiler.

These results are obtained ywithoutin any way sacriiicing those obtained by .my previous vconstruction, namely, .partial cross flow of .thegasesKy -.over the tubes with lthe retention of hot vrefractory surfaces on the lowerrow of tubes in `the most effective ,position to vfacilitate combustion and to Aprevent .smokeformation One form of the invention is illustrated inthe accompanying drawing, wherein:

Figure l .is ,a longitudinal section Jpartly 4in side elevation of a steam boiler. Fig. 2 is a section on .the line II-II of Fig. 1, showing the tile enclosing tubes in the lower row. Fig. .3 is a sec- .tion on the `line IIL-III of Fig. 1, showing tile -laici on top of tubes to form a filter baille.

Referring now to the drawing, I is the front wall of a furnace, 2 is the bridge wall, and 3 theupperpart of the combustion chamber. The water .tubes 4 are located above the furnace and may 'be in one group, as shown, or subdivided into two or more groups, but the .grouping is not material .to my invention. The tubes are connected 'at the rear .end to downtake headers 5 and `at the front end by uptake headers E. The uptake headers are connected to the longitudinal drum by short connections lil `and the downtake headers by along connection 9. In certain forms of boilers a cross drum is'used, but this is not material to my invention.

The baille 'construction consists of five parts 'as follows: 55

l`First, -a yshort longitudinal baille I0, which 'is -ev-ident to those skilled `in the art. ycross baille l5 `converts what would be, with `-the Iusual for-mof construction, a dead gas pocket, in which soot and -ashes vwould accumulate, into constructed of tile that preferably, but not Vvnecessarily, completely surrounds the tubes in the lower row for only apart of their length, so as transfer.

Third. a curved upper'cross baille I2 inclined toward the front header 6 yis used vto reverse the direction of the gases and direct rthemy downward across the tubes, forming with the rear cross 220 baille `a second pass 2|. After a second reversal in the lower :part of the tube -space below the baille I2, Athe .gases again cross the tubes in `the vthird pass 2|) and flow to the outlet I4 of ythe boiler.

Fourth, a straight upper baille I3 is laid, preferably on the :upper row lof tubes, in lorder to prevent the gases which are ascending the :first pass I9 from flowing directly `tothe boiler outflejt I4. This baille'in icon-junction 'with-fthe baffle A*30 AI2 k.directs the gases downwardfinto thesecond pass 2-|.

Fifth, a lcurvedffroni-l cross baille `'I5 connecting with lthe lower longitudinal Ybaille -I 0 and inclined upward across thetubes to a point `on orfadjacent 135 'to lthe A`front header 6, forms --with -the -upper cross baille `==I2, the third pass '20 Iand with the front 'header 6, a fourth pass "|56.

The advantages of this construction will vbe The curved A40 an acti-ve `and 4useful rpart of the boiler. Not only lare the front ends -of the -lower yrows of Vl5 tubes-exposedto the radiant heat 'of the fire, but Bby-leavi-n-ga narrow opening LI"I between the front `cross baille "F5 and the lfront header l6, a small por-tion Jof the hot furnace gases are diverted from the main 'stream-'and caused to flowacross '50 `the'heatingsurface inthe fourth'pass 'I6,`mate rially yincreasing the eifective heating surface of the boiler. A similar narrow opening |18 'between the upper longitudinal 'baille I3 and the rear Lheader L5 diverts a smallport'ion ofthe gas 55 ascending through the rst pass I9 into and through the space between the tubes at the upper rear end of the boiler where an effective flow of gases would not otherwise exist. Ihe longitudinal baille l0 reflects the heat into the gas stream passing below it, and by maintaining a high gas temperature, aids materially in securing complete combustion and in the prevention of smoke.

The curved baille construction in conjunction with the proper proportioning of the various passes vwill maintain a uniformly high velocity of the gases and retain the soot and ash in suspension until clear of the third pass 2D. Suitably located soot blowers at the base of the curved lower bailles will readily keep the tube and baille surfaces clean.

In order to more evenly distribute the hot gases flowing into and through the first pass i9 and through and out of the third pass 2D, illter bailles .22 and 23 may be used in one or both passes and may readily be constructed of loose tile laid on Atop of the tubes in some, but not all, of the alleys or spaces between the tubes. The illter bailles need not be gas tight and may be of such length as may be found necessary to accomplish the desired result. An alternate construction which would produce the same results would be a checker work formed by using tile spaced at intervals in the alleys. It is also evident that the lter baffles may be located in the `passes instead of at the throats, as shown, or may be used alone, or in conjunction With each other, and either or both may be used with either straight or curved cross bailles.

While certain embodiments of the invention are shown in the accompanying drawing, it should be understood that there is a wide variation possible in the types of boilers, in the grouping of their tubes, and in the location of supervheaters (if used), and I do not limit the application of my invention to the exact construction shown unless otherwise limited by the terms of the claims. While curved cross bailles are more effective than straight baiiles, it is evident that straight cross baiiles may be used instead, and I do not limit my claims to one construction only.

What I claim is:

1. In a boiler of the water tube type having a furnace therebeneath and comprising a bank of tubes inclined from front to rear, upright headers Y. at the ends of the tubes and a steam and Water drum above the tubes with which the tubes communicate through the headers, a combustion chamber below the tubes, a longitudinal baille extending along the tubes in the lower row inter- `mediate the ends thereof for a portion only of .their length, a cross baille extending upwardly from the rear end of said longitudinal baille diagonally across the tubes towards the rear header, a second cross baille extending upwardly `frorn the front end of said longitudinal baille diagonally across the tubes toward the front header, a second longitudinal baille on one of the upper rows of tubes extending forwardly a part only of the length of the tubes and a third cross baille extending downwardly from the front end of said upper longitudinal baffle diagonally across the tubes toward the front header.

2. In a boiler of the water tube type, having a furnace therebeneath and comprising a bank of tubes inclined from front to rea-r, upright headers at the ends of the tubes, and a steam and water drum above the tubes with which the tubes communicate through the headers, a combustion chamber below the tubes, a longitudinal baille extending along the tubes of the lower row intermediate the ends thereof for a portion only of their length, a cross baille extending upwardly in a curve across the tubes towards the rear header, a second cross baille extending upwardly in a curve from the front end of said lower longitudinal baille across the tubes toward the front header, a second longitudinal vbaille on top of one of the upper rows of tubes extending forwardly a part only of the length of the tubes and a third cross baille extending in a curve downwardly across the tubes toward the front header.

3. In a boiler of the water tube type, having a furnacetherebeneath and comprising a bank of tubes'inclined from front to rear, upright headers at the ends of the tubes and a steam and water drum above the tubes with which the tubes communicate through the headers, a combustion chamber below the tubes, a longitudinal baille extending along the tubes of the lower row intermediate their ends for a portion only of their length, a cross baille extending upwardly Vfrom the rear end of said longitudinal baille diagonally across the tubes towards the rear header, a second -cross baille extending upwardly from the front end of said longitudinal baille diagonally across the tubes toward the front header, a second longitudinal baille on one of the upper rows of tubes, extending forwardly a part only of the length of the tubes, and a third cross baille extending downwardly from the front end of said upper longitudinal baille diagonally across the tubes towards the front header, a filter baille extending forwardly from the forward end of said second longitudinal baille towards the front header. and a filter baffle extending to the rear from the rear end of the rst mentioned longitudinal baille t0- wards the rear header.

4. In a boiler of the-Water tube type having a furnace therebeneath and comprising a bank of tubes inclined from front to rear, upright headers at the ends of the tubes and a steam and water drum above the tubes with which the tubes communicate through the headers, a combustion chamber below the tubes, a longitudinal baille extending along the tubes in the lowerrow intermediate the ends thereof for a-portion only of their length, a cross baffle extending upwardly from the rear end of said longitudinal baille diagonally across the tubes to a point adjacent the front header but spaced away therefrom, a second longitudinal baille on one of the upper rows of tubes extending forwardly a part only of the length of the tubes and a third cross baille extending downwardly from the front end of said upper longitudinal baille diagonally across the tubes toward the front header.

5. In a boiler of the Water tube type having a furnace therebeneath and comprising a bank of tubes inclined from front to rear, upright headers at the ends of 'the tubes and a steam and Water drum above the tubes with which the tubes communicate through the headers, a combustion Y chamber below the tubes, a longitudinal baille extending along` the tubes in the lower row intermediate the ends thereof for a portion only of their length, a cross baille extending upwardly from the rear end of said longitudinal baille diagonally across the tubes toward the front header, a second longitudinal baille on-A one o f the upper rows of tubes extending forwardly, over a substantial portion of the length of such tubes from a point adjacent to the rear header but spaced away therefrom, and a third cross baie extending downwardly from the front end of said upper longitudinal baffle diagonally across the tubes toward the front header.

6. In a boiler of the water tube type having a furnace therebeneath and comprising a bank of tubes inclined from front to rear, upright headers at the ends of the tubes and a steam and water drum above the tubes with which the tubes communicate through the headers, a combustion chamber below the tubes, a longitudinal baille extending along the tubes in the lower row intermediate the ends thereof for a portion only of their length, a cross baffle extending upwardly from the rear end of said longitudinal baffle diagonally across the tubes towards the rear header, a second cross bale extending upwardly from the front end of said longitudinal balTle diagonally across the tubes to a point adjacent the front header but spaced away therefrom, a second longitudinal baffle on one of the upper rows of tubes extending forwardly over a substantial portion of the length of such tubes from a point adjacent to the rear header but spaced away therefrom, and a third cross baie extending downwardly from the front end of said upper longitudinal baille diagonally across the tubes toward the front header.

KINGSLEY L. MARTIN. 

